Roller shoe

ABSTRACT

A roller shoe has a pliable bottom. Rear wheels are independently rotatable about a rear axle recessed in the heel portion. A front wheel is rotatable on a front axle recessed in the arch portion. Both axles are removably yet firmly supported partially recessed within wheel housings. Rolling with front and rear wheels on a flat skating surface holds the forward portion of the shoe bottom clear of the skating surface. Tilting forward onto the front wheel alone allows pivoting while rolling. Tilting farther forward brings the forward portion down to sliding, standing or walking contact with the skating surface. Tilting backward onto the rear wheels alone allows pivoting while rolling. Tilting backward in the extreme brings the shoe heel into sliding or resting contact with the skating surface. Wheels are formed of urethane, axles and bearings of steel, shoe of textile or leather, shoe bottom of resinous or rubber material, and wheel housings of strong plastic such as nylon.

[0001] This application claims the benefit of prior copending U.S. application Ser. No. 60/353,102, filed Jan. 30, 2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to active and recreational footwear and more particularly to wheeled shoe bottoms, especially to wheels housed partially recessed within a shoe bottom.

[0004] 2. Description of the Related Art

[0005] A roller skate or roller blade typically has wheels mounted on a rigid structure extending downward from a shoe bottom as exemplified by U.S. Pat. No. 4,295,655, a roller skating shoe.

[0006] A sport shoe typically has a pliable, cushioned sole as exemplified by U.S. Pat. No. 4,245,406, an athletic shoe.

[0007] A sport shoe adapted to include a roller or wheel is exemplified by U.S. Pat. No. 6,120,039. Attempts have been made to adapt a roller shoe to be used as a walking shoe as exemplified by U.S. Pat. No. 5,785,327. Another rolling shoe is described by U.S. patent application Ser. No. 2001/001,9195 and U.S. Pat. No. 2001/005,4802 (the '9195 and '4802 applications, respectively). A retractable wheel mechanism can be bulky. Retractable wheels can make a shoe clumsy and heavy. The more frequently the wheels are removed, the greater the chance they will be mislaid and lost.

[0008] In the '9195 and '4802 applications, a single wheel, or tandem wheels functioning as a single wheel, are placed within in the heel portion of the shoe bottom extending partially downward from the sole. A user (“skater”) can shift weight to his or her heel and lifting his or her toe and thus be able to roll. When weight is placed on the forward portion of the shoe, the flat surface of the sole of the shoe comes into contact with the walking surface. Rolling stops and the skater can stand or walk. This single-axle design with wheels in the heel portion has a single balance point, creating a teeter-totter effect whereby the skater's balance must constantly be adjusted. If the skater leans too far forward or rearward, he or she may fall. If a more easily balanced, more versatile, more stable roller-equipped shoe were available, skaters might find less fatigue and frustration and more enjoyment.

SUMMARY OF THE INVENTION

[0009] It is a general object of the present invention to provide a versatile, enjoyable, stable, comfortable, easy-to-use, easy-to-learn roller shoe.

[0010] In accordance with these objects and with others which will be described and which will become apparent, an exemplary embodiment of a roller shoe in accordance with the present invention comprises a shoe upper and a shoe bottom attached thereto. Rear left and right wheels and a front wheel are removably yet securely held partially recessed in wheel housings in the bottom surface of the shoe bottom. The rear left and right wheels contact a skating surface (i.e., any reasonably firm, reasonably flat ground surface such as a driveway, sidewalk, or rink) beneath the heel portion of the shoe bottom. The front wheel contacts the skating surface beneath the arch portion of the shoe bottom. The three points of contact with the skating surface define a plane. In an exemplary embodiment of a roller shoe in accordance with the present invention, that plane passes entirely beneath the shoe bottom and does not intersect the shoe bottom.

[0011] When all three wheels are weighted, the skater can roll and can also enjoy the benefits of longitudinally separate wheel locations. These benefits include reduced fatigue in keeping the forward portion of the shoe bottom clear of the skating surface and reduced sensitivity to bumps.

[0012] When only the front wheel is weighted, the skater can roll on the front wheel, tilt forward until the forward portion of the shoe bottom touches the skating surface (causing friction), or pivot with very little torque, all with subtle, barely observable changes in the angle of the shoe bottom relative to the skating surface. The skater enjoys the benefits of a roller shoe whose forward portion is substantially available for stopping the rolling motion and for standing and walking.

[0013] When only the rear wheels are weighted, the skater can roll or can pivot with very little torque, enjoying the benefit of left and right rear wheels mounted on independent bearings.

[0014] In a preferred embodiment, the front wheel is of smaller diameter than the diameter of the rear wheels and the front axle is placed at about the same height as the rear axle. The front wheel can be placed forward of the rear wheels and beneath the arch portion. Having less height, the front wheel requires less vertical clearance, permitting the shoe bottom to be thinner in the arch than in the heel. This can make the shoe more comfortable and can also urge the user into a slightly forward position, depending on the angle of the insole of the shoe.

[0015] The wheels themselves are attached to the sole of the shoe and are partially recessed within the sole. The wheels are positioned on the sole such that roughly 65% of the surface of the sole forms a walking surface.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] For a further understanding of the objects and advantages of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawing, in which like parts are given like reference numbers and wherein:

[0017]FIG. 1 is a bottom perspective view of the roller shoe in accordance with the present invention;

[0018]FIG. 2 is a bottom plan view thereof;

[0019]FIG. 3 is a bottom plan view of the shoe bottom and wheel assemblies thereof;

[0020]FIG. 4 is a rear elevational view thereof;

[0021]FIG. 5 is a rear elevational view thereof;

[0022]FIG. 6 is a side elevational view thereof;

[0023]FIG. 7 is a side elevational view thereof;

[0024]FIG. 8 is bottom sectional view thereof;

[0025]FIG. 9 is a bottom perspective view thereof;

[0026]FIG. 10 is partial rear sectional view thereof;

[0027]FIG. 11 is partial side sectional view thereof;

[0028]FIG. 12 is a partial side cut-away view thereof;

[0029]FIG. 13 is partial side cut-away view thereof;

[0030]FIG. 14 is a partial side cut-away view thereof;

[0031]FIG. 15 is a partial rear cut-away view thereof;

[0032]FIG. 16 is partial rear cut-away view thereof;

[0033]FIG. 17 is partial rear cut-away view thereof;

[0034]FIG. 18 is a partial perspective view thereof;

[0035]FIG. 19 is a partial perspective view thereof; and

[0036]FIG. 20 is a partial bottom sectional view thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] The invention will now be described with reference to FIG. 1, which illustrates in bottom perspective view a preferred embodiment of the roller shoe 40 in accordance with the present invention shown generally by the reference number 40 comprising a shoe upper 52 and a shoe bottom 54. The shoe bottom 54 forms a left side 60, a right side 62, a top surface 56, a bottom surface 58, a front end 64, a rear end 66, a heel portion 68, an arch portion 70, and a forward portion 72. The forward portion 72 of the shoe bottom 54 forms a front stopping surface 74. The heel portion 68 forms a rear stopping surface 76. The arch portion 70 of the shoe bottom 54 forms a front wheel housing 78 in which is disposed a front wheel assembly 82 comprising a front wheel 86 having a front wheel periphery 92. The heel portion 68 of the shoe bottom 54 forms a rear wheel housing 80 in which is disposed a rear wheel assembly 84 comprising a rear left wheel 88 having a rear left wheel periphery 94 and a rear right wheel 90 having a rear right wheel periphery 96.

[0038] With continued reference to FIG. 1, the shoe upper 52 comprises laces 53 which are adapted to fastening the shoe upper 52 to a person's foot. The shoe upper 52 is formed of leather, textiles, thermoplastic and thermosetting resins, rubber, or subcombinations of these and other materials common in the manufacture of footwear. Stitching, welding, adhesives, Velcro® brand adherent strips, and various interference-fitting fasteners may be used to assemble the shoe upper 52 in ways well known to shoemakers. In similar manner, the shoe upper 52 is joined to the top surface 56 of the shoe bottom 54 to form the roller shoe 40.

[0039] With continued reference to FIG. 1, the shoe bottom 54 is made of materials comparable to those of the shoe upper 52, although tending to incorporate fewer textiles and more rubber and other resinous materials. The shoe bottom 54 is generally thick enough and elastic enough to serve as a cushioned shoe for standing, walking, running and jumping. The shoe bottom 54 in this embodiment of the present invention is approximately two inches thick at the heel and approximately ¾ inch thick at the toe. The bottom surface 58 of the shoe bottom 54 generally is formed of a water-impervious, wear-resistant material suitable for outdoor as well as indoor use. The bottom surface 58 may form treads or other functional features. The bottom surface 58 may form ornamental features.

[0040] With continued reference to FIG. 1, the forward portion 72 of the shoe bottom 54—generally, that large flat or gently curved portion of the shoe bottom 54 that is between the arch portion 70 of the shoe bottom 54 and the front end 64 of the shoe bottom 54—may be stood upon or walked upon by a person is placing weight on the ball or toes of the foot. The front wheel 86, rear left wheel 88, and rear right wheel 90 are oriented to permit forward and rearward rolling motion on a relatively smooth walking surface (or skating surface) and are located so as to support the heel portion 68 and the arch portion 70 of the shoe bottom 54 a short distance above such a walking surface. It will be appreciated that a person wearing the roller shoe 40 may allow weight to be borne by the rear wheel assembly 84 either alone or in combination with the front wheel assembly 82. It will also be appreciated that the person may use the rear left wheel 88 and rear right wheel 90 as a fulcrum and rotate the front end 64 of the roller shoe 40 upward until the rear stopping surface 76 of the heel portion 68 touches the walking surface. This maneuver may slow or stop any rolling motion of the roller shoe 40. Alternatively, the person may shift enough weight to the forward portion 72 of the shoe bottom 54 that the forward stopping surface touches the walking surface. This maneuver, too, may slow or stop any rolling motion of the roller shoe 40, and may under some circumstances result in a convenient and graceful transition from rolling motion to walking motion.

[0041]FIG. 2 shows a bottom plan view of an embodiment of the roller shoe 40 in accordance with the present invention shown generally by the reference number 40, comprising the left side 60, the right side 62, the bottom surface 58, the front end 64, the rear end 66, the heel portion 68, the arch portion 70, the forward portion 72, the front stopping surface 74, the rear stopping surface 76, the front wheel housing 78, the front wheel assembly 82, the front wheel 86 and front wheel periphery 92, the rear wheel housing 80, the rear wheel assembly 84, the rear left wheel 88 and rear left wheel periphery 94, and the rear right wheel 90 and rear right wheel periphery 96. The front wheel assembly 82 comprises a front axle 98 which defines a front wheel axis of rotation indicated by arrow Y1. The rear wheel assembly 84 comprises a rear axle 100 which defines a rear wheel axis of rotation indicated by arrow Y2.

[0042]FIG. 3 shows a bottom plan view as in FIG. 2 above after the front wheel assembly 82 and the rear wheel assembly 84 have been removed and placed proximate the right side 62 of the shoe bottom 54 (the left shoe of a pair being shown). The front wheel 86 is mounted on a front axle 98 having axially extending front left axle end 102 and front right axle end 104. The rear left wheel 88 and the rear right wheel 90 are both mounted on a rear axle 100 having axially extending rear left axle end 106 and rear right axle end 108. The front wheel 86 has a diameter smaller than the diameter of the rear left wheel 88 and of the rear right wheel 90. As will be discussed in greater detail with reference to this and other drawing Figures, the front wheel housing 78 is formed in the arch portion 70 of the shoe bottom 54. The rear wheel housing 80 is formed in the heel portion 68 of the shoe bottom 54. The front wheel housing 78 comprises a front left axle support 122 formed to receive the front left axle end 102 and front right axle support 132 formed to receive the front right axle end 104. The rear wheel housing 80 forms a rear left axle support 142 formed to receive a rear left axle end 106 and a rear right axle support 152 formed to receive rear right axle end 108.

[0043]FIG. 4 shows a rear elevational view of the roller shoe 40 in accordance with the present invention shown generally by the reference number 40, comprising the left side 60, the right side 62, the bottom surface 58, the rear end 66, the top surface 56 of the shoe bottom 54 as seen at the rear end 66 of the shoe bottom 54, the heel portion 68, the rear stopping surface 76, the front wheel 86 and front wheel periphery 92, the rear left wheel 88 and rear left wheel periphery 94, and the rear right wheel 90 and rear right wheel periphery 96.

[0044]FIG. 5 shows a rear elevational view of the roller shoe 40 in accordance with the present invention shown generally by the reference number 40, comprising the left side 60, the right side 62, the bottom surface 58, the rear end 66 of the shoe bottom 54, the top surface 56 of the shoe bottom 54 as seen at the rear end 66 of the shoe bottom 54, the heel portion 68, the front wheel 86 and front wheel periphery 92, the rear left wheel 88 and rear left wheel periphery 94, and the rear right wheel 90 and rear right wheel periphery 96. The rear wheel housing 80 is shown located within the shoe bottom 54 approximately midway between the left side 60 and the right side 62 of the shoe bottom 54. The rear wheel housing 80 comprises a horizontally extending rear crossmember 166. The rear wheel housing 80 comprises a downward-projecting rear left support column 116 and a downward-projecting rear right support column 114, which, respectively, form the rear left axle end 106 support and the rear right axle end 108 support. Similarly, the front wheel housing 78 is shown located within the shoe bottom 54 approximately midway between the left side 60 and the right side 62 of the shoe bottom 54. The front wheel housing 78 comprises a horizontally extending front crossmember 164. The front wheel housing 78 comprises a downward-projecting front left support column 112 and a downward-projecting front right support column 110, which, respectively, form the front left axle support 122 and the front right axle support 132.

[0045] With continued reference to FIG. 5, the rear axle 100 extends between the rear left axle support 142 and the rear right axle support 152. The rear left wheel 88 and the rear right wheel 90 are located midway on the rear axle 100, side-by-side, slightly separated. The front wheel 86 is located midway on the front axle 98. As shown in broken lines in this figure, the front axle 98 and the rear axle 100 are approximately superimposed, as are the front wheel housing 78 and the rear wheel housing 80, and the front wheel 86 and the rear left wheel 88 and the rear right wheel 90. The front axle 98 defines a front wheel axis of rotation indicated by arrow Y1. The rear axle 100 defines a rear wheel axis of rotation indicated by arrow Y2. Y1 and Y2 are approximately superimposed on one another in this view.

[0046] With continued reference to FIG. 5, three broken lines show the approximate height of the top surface 56 of the shoe bottom 54 at L1 above the rear wheel housing 80, at L2 above the front wheel housing 78, and at L3 above the forward portion 72. As shown, in this embodiment, the front crossmember 164 is not located as far upward within the shoe bottom 54 as does the rear wheel housing 80. Also as shown, in this embodiment, the front wheel 86 has a diameter smaller than that of the rear left wheel 88 and the rear right wheel 90. It will be appreciated that this arrangement allows the front wheel periphery 92 to extend a shorter distance downward beneath the bottom surface 58 than do the rear left wheel periphery 94 and the rear right wheel periphery 96, while, at the same time, the front wheel periphery 92 extends a shorter distance upward above the shoe bottom 54 periphery. This shorter upward extent of the front wheel periphery 92 allows the front wheel housing 78 to require less vertical clearance within the shoe bottom 54 than does the rear wheel housing 80. As a result, the top surface 56 of the shoe bottom 54 may describe a natural arch contour, declining as it extends forward from the rear end 66, through L1, L2, and L3, to form a comfortable roller shoe 40 having a mildly elevated heel portion 68 and a supportive arch portion 70, even while providing for a front wheel periphery 92 extending a shorter distance downward from the bottom surface 58 of the shoe bottom 54 than the rear left wheel periphery 94 and the rear right wheel periphery 96 extend. Thus, the preferred embodiment of the roller shoe 40 in accordance with the present invention can be positioned on all three wheels, roughly level or toe slightly lowered relative to the skating surface, and with the forward portion 72 held slightly above the skating surface. It should be noted that the apparent uppermost portion of the shoe bottom 54, or “top surface 56 of the shoe bottom 54,” as viewed on the outside of the rear end of the shoe referred to above, might not coincide with level L1 on the inside. This might happen, for example, where an outer portion of a shoe bottom wraps upward upon a portion of an outer surface of a shoe upper.

[0047]FIG. 6 shows a side view of the right side of the heel portion 68 and the arch portion 70 of the shoe bottom 54 in the preferred embodiment of the roller shoe 40 in accordance with the present invention, comprising the top surface 56, the bottom surface 58, the rear end 66, the rear stopping surface 76, the front wheel 86 and front wheel periphery 92, and the rear right wheel 90 and rear right wheel periphery 96. The rear left wheel 88 and rear left wheel periphery 94 are not shown, being obscured by the rear right wheel 90.

[0048]FIG. 7 shows a side elevational view of the right side of the roller shoe 40 in accordance with a preferred embodiment of the present invention including the heel portion 68 and the arch portion 70 of the shoe bottom 54, the top surface 56, the bottom surface 58, the rear end 66, and the rear stopping surface 76. The front wheel housing 78 comprises the front crossmember 164 and the downward-projecting front right support column 110 (the front left support column 112, not shown, being superimposed thereon). Similarly, the rear crossmember 166 comprises the downward-projecting rear right support column 114 (the rear left support column 116, not shown, being superimposed thereon). The front right support column 110 forms the front right axle support 132, which will be described in greater detail as a leftward-facing, downward opening slot formed in the front right support column 110. In similar fashion, the rear right support column 114 forms the rear right axle support 156. The front left axle support 122 (not shown) and the rear left axle support 142 (not shown) are formed and located as mirror images of their right-handed counterparts.

[0049] With continued reference to FIG. 7, the front wheel assembly 82 is removably mounted within the front wheel housing 78 as follows: the front right axle support 132 receives the front right axle end 104, which is shown disposed therein, which is insertable therein from below, and which is interference-fitted firmly therein, such that a person must pull downward with approximately five to fifteen pounds force or push strongly from one side while pulling strongly downward in order to dislodge the front right axle end 104 and the front left axle end 102 from the front wheel housing 78. In similar manner, the rear wheel assembly 84 is mounted within the rear wheel housing 80.

[0050] With continued reference to FIG. 7, the front crossmember underside 118 is spaced apart from the front wheel periphery 92 and the rear crossmember underside 120 is spaced apart from the rear right wheel periphery 96 and the rear left wheel periphery 94 (not shown). The rear left support column 116 (not shown) is taller than the front left support column 112 (not shown). The rear right support column 114 is taller than the front right support column 110. As a result, the rear crossmember 166 is higher above the bottom surface 58 of the shoe bottom 54 than is the front crossmember 164, while the rear right axle end 108, the rear left axle end 106 (not shown), the front right axle end 104, the front left axle end 102 (not shown), and the axle supports that receive them, are all located at approximately the same height above the bottom surface 58 of the shoe bottom 54. The top surface 56 of the shoe bottom 54 is located above and relatively near to the front crossmember 164 and the rear crossmember 166.

[0051] With continued reference to FIG. 7, A-A defines a plane coinciding with the bottom surface 58 of the shoe bottom 54 in the heel portion 68 and the arch portion 70 thereof. The forward portion 72 of the shoe bottom 54 extends forward while curving gently upward above plane A-A. Z defines the vertical axis as being normal to plane A-A. B-B defines a tangent of the front wheel periphery 92 and either the rear right wheel periphery 96 or the rear left wheel periphery 94. B-B passes beneath the shoe bottom 54 and does not intersect the shoe bottom 54. C-C defines a tangent of the front wheel periphery 92 and the forward portion 72 of the upwardly-curving shoe bottom 54. D-D defines a tangent of the rear right wheel periphery 96 or the rear left wheel periphery 94. D-D passes beneath the shoe bottom 54 and does not intersect the shoe bottom 54. E-E defines a tangent of the rear end 66 of the shoe bottom 54 and the rear right wheel periphery 96 or the rear left wheel periphery 94.

[0052] A person using the roller shoe 40 in accordance with the present invention (we shall call this person “the skater”) can wear it with the front wheel assembly 82, the rear wheel assembly 84, both of them, or neither of them, installed.

[0053] With neither of the wheel assemblies installed, the skater can walk normally.

[0054] Installing only the rear wheel assembly 84 in each roller shoe 40 (both the left and right shoe), the skater can roll, walk, or do both. On a reasonably hard, reasonably flat skating surface (a sidewalk, floor, ramp, driveway, or the like), when the skater lifts the toe portion of a roller shoe 40 away from the skating surface, the weight placed on that shoe is transmitted by the rear axle 100 (coinciding with the rear wheel axis of rotation) to the rear left wheel 88 and the rear right wheel 90. Oriented as they are in the shoe bottom 54 for forward and backward rolling motion, the rear left wheel 88 and the rear right wheel 90 will tend to allow the roller shoe 40 to continue to roll, forward or backward as the case may be, until some force alters this rolling motion. Such a force can result from gravity on a hill, from rolling friction, from the skater pushing or stopping with the other foot, or from contact of the roller shoe 40 with the skating surface.

[0055] The roller shoe 40 can contact the skating surface in at least two ways. With only the rear wheel assembly 84 installed, if the roller shoe 40 is rotated sufficiently forward (toe down) about the rear wheel axis of rotation, the bottom surface 58 of the forward portion 72 of the shoe bottom 54 will touch the skating surface. The resulting sliding friction will slow or stop the rolling motion of the roller shoe 40. The part of the bottom surface 58 of the forward portion 72 that tends most often to touch the skating surface is referred to as the front stopping surface 74. If the shoe is rotated sufficiently rearward (toe up) about the rear wheel axis of rotation, the bottom surface 58 of the heel portion 68 of the shoe bottom 54, proximate the rear end 66 of the shoe bottom 54, will touch the skating surface. The resulting sliding friction will slow or stop the rolling motion of the roller shoe 40. The part of the bottom surface 58 of the heel portion 68 that tends most often to touch the skating surface is referred to as the rear stopping surface 76.

[0056] With only the rear wheel assembly 84 installed in each roller shoe 40, the skater can roll continuously by holding both roller shoes at intermediate orientations such that neither the front stopping surfaces nor the rear stopping surfaces touch the skating surface. If the skater becomes unbalanced, he or she must reposition one or both roller shoes beneath his or her center of mass in order not to fall. In order to stabilize his or her center of mass relative to the support he or she receives from the two roller shoes, the skater may prefer to position one foot forward (“front foot”) and one foot rearward (“back foot”).

[0057] In this front foot and back foot position, if a forward-rolling skater's center of mass gets too far behind both roller shoes, he or she may raise the toe of the front foot or the rear foot or both, thereby engaging one or both rear stopping surfaces, retarding the forward motion of one or both roller shoes until his or her center of mass is more stably supported.

[0058] In this front foot and back foot position, if a forward-rolling skater's center of mass gets too far ahead of both roller shoes, he or she may, through a deliberate change of posture and leg position, move one roller shoe 40 to a new front foot position. Otherwise, the skater will tilt forward until, eventually, at least one roller shoe 40 has rotated forward sufficiently that its front stopping surface 74 touches the skating surface. Friction will then retard the forward motion of that roller shoe 40. A likely result will be that the skater's center of mass will be even less stably positioned, farther ahead of the support provided by the roller shoes, whereupon even greater physical effort will be required in order to return to stable rolling motion.

[0059] Whether the skater's feet are positioned front and back or side by side, the skater must use muscular tension to stabilize both roller shoes at intermediate angles about the rear wheel axis of rotation such that neither front stopping surface 74 touches the skating surface. The farther forward the skater's center of mass relative to the support provided by the roller shoes, the more powerfully the skater will have to contract the muscles that raise his or her foot toward a toes-up position. The skater's reliance on muscular tension alone to stabilize both roller shoes at such intermediate angles has two consequences. First, the skater must develop sufficient muscular power to stabilize the roller shoes at the intermediate angles. Second, the skater must develop the skill and coordination to do so. Both the muscular power and the skill and coordination are developed over time. A novice skater who becomes frustrated and quits early might miss out on the enjoyment of the roller shoes.

[0060] Using the preferred embodiment of the roller shoe 40 in accordance with the present invention, the skater can install both the rear wheel assembly 84 and the front wheel assembly 82. With both wheel assemblies installed, if the skater becomes unbalanced in the forward direction, such that his or her center of mass has moved ahead of the support provided by the roller shoes, the front wheel assembly 82 provides the skater an additional means of stabilizing one or both roller shoes at intermediate angles about the rear wheel axis of rotation such that neither of the front stopping surfaces touches the skating surface.

[0061] With reference to the side view of FIG. 7, it will be noted that the skater may, as set forth above, use muscular tension to stabilize the roller shoe 40 at an intermediate angle such that the front stopping surface 74 does not touch the skating surface. However, as the skater rotates the roller shoe 40 forward about the rear wheel axis of rotation within the aforementioned range of intermediate angles, an angle is attained at which the front wheel periphery 92 touches the skating surface. As the skater progressively transfers weight from rear left wheel periphery 94 and the rear right wheel periphery 96 onto the front wheel periphery 92, a new, more forward, point of support is established beneath the arch portion 70 of the shoe bottom 54.

[0062] With continued reference to FIG. 7, the consequences are several. The support provided by the roller shoe 40 is moved forward relative to the skater's center of mass, aiding the skater in regaining or maintaining a position of stable balance while rolling. Additionally, because the front wheel 86 is located forward of the rear left wheel 88 and the rear right wheel 90, the support provided at the front wheel axis of rotation tends greatly to lessen the amount of muscular tension needed to stabilize the roller shoe 40 at an intermediate angle such that the forward stopping surface does not touch the skating surface. Moreover, if the skating surface has any irregularities, they are less likely to perturb the angle of the roller shoe 40 or the balance of the skater. Any one irregularity in the skating surface is unlikely to be encountered by all wheels at the same time, because the front wheel periphery 92 will likely encounter it before the rear wheels do. Two successive smaller shocks are less disturbing than one larger one.

[0063] Contrastingly, if the front wheel assembly 82 were removed, a bump in the skating surface during forward rolling motion might cause the roller shoe 40 to rotate forward about the rear wheel axis of rotation to an angle at which the front stopping surface 74 touches the skating surface. Even if this angle is maintained only momentarily, the resulting friction tends to force the skater's foot rearward relative to his or her knee and hip. As a result, the roller shoe 40 will tend to rotate farther forward, increasing the magnitude, duration and frequency of disturbances resulting from such a bump.

[0064] However, with the front wheel assembly 82 installed, the same bump will first cause a transfer of weight onto the front wheel 86. Only after that, would the bump, if severe enough, cause the roller shoe 40 to rotate forward, about the front wheel axis of rotation, to an angle such that the front stopping surface 74 touches the skating surface. Thus, the preferred embodiment of the roller shoe 40 in accordance with the present invention limits or relieves muscular fatigue and frustration.

[0065] With the rear wheel assembly 84 and the front wheel assembly 82 installed, the preferred embodiment of the roller shoe 40 in accordance with the present invention enhances the skater's ability to pivot. It will be noted that the skater can hold the roller shoe 40 at an angle such that only the left rear wheel periphery and the right rear wheel periphery touch the skating surface. Because separate sets of bearings 168 independently affix the left rear wheel and the right rear wheel to the rear axle 100, the left rear wheel and the right rear wheel are free to rotate in opposite directions. Consequently, the skater may pivot easily and smoothly while holding the roller shoe 40 at such an angle.

[0066] With the rear wheel assembly 84 and the front wheel assembly 82 installed, it will also be noted that the skater can transfer weight from the rear axle 100 to the front axle 98 until the roller shoe 40 begins to rotate forward about the front wheel axis of rotation. As can be seen in FIG. 7, there is a range of angles at which neither the rear left wheel periphery 94, nor the rear right wheel periphery 96, nor the front stopping surface 74, nor the rear stopping surface 76, touches the skating surface. At such angles, the skater can pivot easily and smoothly. The skater may well prefer to do so, for these angles are the first ones encountered as the skater makes a transition from walking (or standing) to rolling.

[0067] With the rear wheel assembly 84 and the front wheel assembly 82 installed, the preferred embodiment of the roller shoe 40 in accordance with the present invention enhances the skater's ability to make graceful transitions between rolling and walking. Those transitions occur when the front wheel 86 is carrying weight. The front wheel 86 is closer to the front stopping surface 74 than is the rear wheel. Consequently, a given change in the angle of the roller shoe 40 about the front wheel axis of rotation relative to the skating surface will produce a smaller change in the clearance between the front stopping surface 74 and the skating surface. It is thus easier for the skater to modulate the friction that results, and hence easier for the skater to make a smooth transition between rolling and walking. In some situations, the skater might place a high value on making a smooth transition between rolling and walking. For example, the skater might prefer not to draw attention to the fact that the shoes are roller shoes instead of ordinary shoes, and might therefore prefer to avoid making jerky movements. In some situations, the skater might prefer to make transitions between walking and rolling motion without stopping to uninstall or remove any of the wheel assemblies. Thus, it is advantageous that all of the wheels of the preferred embodiment of the roller shoe in accordance with the present invention are located such that the forward portion 72 of the shoe bottom 54 is available for walking or standing. Contrastingly, a roller skate, even if equipped with a toe brake, does not have a forward surface readily available for walking or standing.

[0068] With reference again to FIG. 3, the front wheel housing 78 is formed in the arch portion 70 of the shoe bottom 54 and is shaped to hold the front crossmember 164 (not shown), the front left support column 112 (not shown), and the front right support column 110 (not shown) while providing clearance for the front wheel assembly 82 (not shown). Likewise, the rear wheel housing 80 is formed in the heel portion 68 of the shoe bottom 54 and is shaped to hold the rear crossmember 166 (not shown), the rear left support column 116 (not shown), and the rear right support column 114 (not shown) while providing clearance for the rear wheel assembly 84 (not shown). The material of the bottom surface 58 of the shoe bottom 54 may also form the surfaces of the front wheel housing 78 and the rear wheel housing 80. The material of the shoe bottom 54 itself may be thickened, hardened, or reinforced as needed to strengthen the front wheel housing 78 and the rear wheel housing 80.

[0069]FIG. 8 shows a bottom sectional view of the heel portion 68 and the arch portion 70 of the shoe bottom 54 in the preferred embodiment of the roller shoe 40 in accordance with the present invention, comprising the front wheel housing 78, the front crossmember 164, the front right support column 110, and the front left support column 112 (which may be regarded as a mirror image of the right). The front left support column 112 forms an inner surface which is inscribed to form a front prong 124, a rear prong 126, a lateral surface 128, and an arch 130, thus defining the front left axle support 122. Similarly, the front right support column 110 forms an inner surface which is inscribed to form a front prong 134, a rear prong 136, a lateral surface 138, and an arch 140, thus defining the front right axle support 132. In like manner, the rear left support column 116 forms an inner surface which is inscribed to form a front prong 144, a rear prong 146, a lateral surface 148, and an arch 150, thus defining the rear left axle support 142; and the rear right support column 114 forms an inner surface which is inscribed to form a front prong 154, a rear prong 156, a lateral surface 158, and an arch 160, thus defining the rear right axle support 152.

[0070] With continued reference to FIG. 8, the front crossmember 164, front left support column 112, and front right support column 110 fit snugly into the front wheel housing 78. Similarly, the rear crossmember 166, rear left support column 116, and rear right support column 114 fit snugly into the rear wheel housing 80.

[0071]FIG. 9 shows a bottom perspective view of the heel portion 68 of the shoe bottom 54 in the preferred embodiment of the roller shoe 40 in accordance with the present invention, comprising the rear wheel housing 80, the rear crossmember 166, and the rear left support column 116. The front prong 144, the rear prong 146, the lateral surface 148, and the arch 150 form the rear left axle support 142.

[0072]FIG. 10 is a composite rear sectional view of the rear left support column 116, the rear crossmember 166 (to the midpoint thereof, the front crossmember 164 (to the midpoint thereof), and the front right support column 110, each section being taken at the highest extent of the arch 150 formed in the rear left support column 116 or of the arch 140 formed in the front right support column 110. The rear left support column 116 forms the arch 150 and the lateral surface 148 of the rear left axle support 142. Similarly, the front right support column 110 forms the arch 140 and the lateral surface 138 of the front right axle support 132. The rear left support column 116 (and its right counterpart, not shown) is taller than the front right support column 110 (and its left counterpart, not shown). The rear left support column 116 is formed integrally with the rear crossmember 166 and the rear right support column 114 (not shown). Similarly, the front right support column 110 is formed integrally with the front crossmember 164 and the front left support column 112 (not shown).

[0073]FIG. 11 shows a side sectional view, as seen from the right, of the front left support column 112 with front prong 124, rear prong 126, lateral surface 128, and arch 130; the front crossmember 164, the rear left support column 116 with front prong 144, rear prong 146, lateral surface 148, and arch 150; and a top surface member 162 of the shoe bottom 54 (not shown). As illustrated, the top surface member 162 is formed separately from the front crossmember 164 and the rear crossmember 166. This being so, the front crossmember 164 and the rear crossmember 166 may be inserted into a shoe bottom 54 (not shown) that has previously been molded with the top surface member 162 in place. A weld, an adhesive, or an interference fit may be used to immobilize the front crossmember 164 within the front wheel housing 78 (not shown) and the rear crossmember 166 within the rear wheel housing 80 (not shown). Alternatively, the front crossmember 164 and the rear crossmember 166 may first be joined to the top surface member 162 or formed integrally with the top surface member 162. The balance of the shoe bottom 54 (not shown) may then be formed around these structures or they may be inserted into the balance of the shoe bottom 54 (not shown) from above.

[0074] With continued reference to FIG. 11, the front crossmember 164, rear crossmember 166, front left support column 112 (not shown), front right support column 110 (not shown), rear left support column 116 (not shown), and rear right support column 114 (not shown), and top surface member 162 of the preferred embodiment of the roller shoe 40 are formed by injection molding, casting, or other common methods from nylon, metal, or other suitably tough and durable material. In a preferred embodiment, the material for the wheel housing is injection grade plastic (NANYA 8018), the injection plastic housing is inserted from the top of the outsole, the outsole is made of compression molded rubber and the housing is sandwiched between the outsole and the upper of shoe.

[0075]FIG. 18 shows a perspective view of a preferred embodiment of the roller shoe in accordance with the present invention including the shoe bottom 54 in which are formed the front wheel housing 78 and the rear wheel housing 80. Shown located above the shoe bottom 54 is the top surface member 162 and, formed integrally therewith, the rear left support column 116, the front left support column 112, and the front right support column 110 which forms the front prong 124, the rear prong 126 and the lateral surface 128.

[0076]FIG. 19 shows the view of FIG. 18 after the top surface member 162 has been lowered onto the shoe bottom 54 such that the support columns are in their final locations within the wheel housings in the shoe bottom.

[0077] In a preferred embodiment, the material for the wheel housing is injection grade plastic (NANYA 8018), a propylene copolymer chosen for strength and support. More particularly, the material used is polyamide 6 mixed with ethylene. The wheel housing is set from the inner side of the outsole with its edges hung and fit the outsole rubber blocks which we make more supportive by higher physical properties. The thick and hard insole material between upper and the outsole supports the housing from the pressure of riding. The outsole has very high density EVA filler to give the best cushion.

[0078] In a preferred embodiment of a roller shoe in accordance with the present invention, the materials are as follows:

[0079] Wheel

[0080] polyester polyol (PTMEG): 53%

[0081] diphenylmethane-4,4′-diisocyanate: 32%

[0082] chain extender: 8%

[0083] reaction regulant (DSE-535T): 3%

[0084] silicone surfactant (DSE 200C): 2%

[0085] antioxidant (DSE-71710): 1%

[0086] amine catalyst: 1%

[0087] Outsole (Rubber)

[0088] TTR-5L (natural rubber): 18%

[0089] 1502 (synthetic rubber): 18%

[0090] BR-01 (synthetic rubber): 30%

[0091] ZEOSIL#155: 23%

[0092] SI-69 (abrasion improvement): 3%

[0093] M (acceleration): 3%

[0094] DM (acceleration): 3%

[0095] P-OIL: 2%

[0096] Axle

[0097] Steel 45C

[0098] Injection

[0099] polyamide 6: 92%

[0100] ethylene propylene copolymer: 5.60%

[0101] polyolefin resin: 1.26%

[0102] dispersion agent (ethylene bis stearamide): 0.80%

[0103] lubricant (AC 540): 0.14%

[0104] stabilizer agent (1010): 0.20%

[0105] Hub

[0106] polycarbonate

[0107] In a preferred embodiment, the plastic housing is inserted from the top of the outsole. The outsole is made of compression molded rubber. The housing is sandwiched between the outsole and the upper of shoe.

[0108] In a preferred embodiment, the wheels are made from polyurethane and comprise a contained core made from polycarbonate. The bearings are ABEC-5 chrome bearings. The axle is formed of steel 45C. Snap rings are used to hold the bearings on the axle.

[0109]FIG. 12 shows a side cut-away view of the roller shoe in accordance with the present invention including the front left support column 112, the front crossmember 164, the top surface member 162, and the rear left support column 116. The front left support column 112 forms the front prong 124, the rear prong 126, the arch 130, and the lateral surface 128. Similarly, the rear left support column 116 forms the front prong 144, the rear prong 146, the arch 150, and the lateral surface 148. The front left axle end 102 is shown located directly beneath the arch 130. The rear left axle end 106 is shown located directly beneath the arch 150.

[0110]FIG. 13 shows the side cut-away view of FIG. 12 as the front left axle end 102, when move upward toward the arch 130, urges the front prong 124 c and the rear prong 126 apart from one another. Elastic deformation of the front prong 124, the rear prong 126, and the front left support column 112 that forms them is accompanied by pressure and friction which resists the vertical movement of the front left axle end 102 relative to the front left support column 112.

[0111]FIG. 14 shows the side cut-away view of FIGS. 12 and 13 after the front left axle end 102 has been thrust into contact with the arch 130. So positioned, the front left axle end 102 is capable of bearing a generally downward force corresponding to the loads the roller shoe 40 exerts upon it during use. So positioned, the front left axle end 102 is immobilized relative to the front left support column 112 due to the aforementioned friction. Strong pulling, shoving, or prying is necessary to remove the front left axle end 102 from this position.

[0112] With continued reference to FIG. 12, FIG. 13, and FIG. 14, the rear left axle end 106 fits proximate the arch 150. In the same manner, the opposite axle ends, namely the front right axle end 104 and the rear right axle end 108, fit and are immobilized proximate the arches 140 and 160 (not shown) of the front and rear right support columns 110 and 114 (also not shown).

[0113]FIG. 15 shows a rear cut-away view of the roller shoe in accordance with the present invention including the rear crossmember 166, the rear left support column 116 and arch 150, the rear right support column 114 and arch 160, the rear left axle end 106, the rear right axle end 108, and the rear left wheel 88 and rear right wheel 90. The rear left axle end 106 and the rear right axle end 108 are shown located directly beneath the arches 150 and 160, respectively.

[0114]FIG. 16 shows the view of FIG. 15 as the rear left axle end 106 and the rear right axle end 108 are thrust upward toward the arches 150 and 160, contacting the lateral side surfaces 148 and 158, respectively, urging the rear left support column 116 and the rear right support column 114 apart from one another. Elastic deformation of rear left support column 116, the rear right support column 114, and the rear crossmember 166 that forms them is accompanied by pressure and friction between the rear left axle end 106 and the lateral surface 148, and likewise between the rear right axle end 108 and the lateral surface 158, which resists the vertical movement of the rear axle ends 106 and 108 relative to the rear support columns 116 and 114.

[0115]FIG. 17 shows the view of FIGS. 15 and 16 after the rear axle ends 106 and 108 have been thrust into contact with the arches 150 and 160 of the rear support columns 116 and 114. So positioned, the axle ends are immobilized relative to the rear support columns 116 and 114 due to the aforementioned friction. As already indicated with reference to the front axle ends with reference to FIGS. 12, 13, and 14, strong pulling, shoving, or prying is necessary to remove the rear axle ends 106 and 108 from this position.

[0116] With continued reference to FIGS. 15, 16 and 17, and also with reference to FIGS. 1, 12, 13 and 14, the two types of elastic deformation are both important in immobilizing both the front axle 98 and the rear axle 100. With particular reference to FIGS. 15, 16 and 17, it will be appreciated that the bulk properties of the shoe bottom material that surrounds the support columns 110, 112, 114 and 116, as well as the snugness with which that material surrounds the support columns, will influence the extent to which the friction between the axle ends 102, 104, 106 and 108 and the respective lateral surfaces 128, 138, 148 and 158 contributes to immobilizing the axles 98 and 100 within the wheel housings 78 and 80.

[0117]FIG. 20 shows a bottom sectional view of the heel portion 68 and the arch portion 70 of the shoe bottom 54 in the preferred embodiment of the roller shoe 40 in accordance with the present invention, including the front wheel housing 78 with the front wheel assembly 82 installed. The front right support column 110 with front prong 134, rear prong 136 and lateral surface 138 forms the front right axle support 132. Similarly, the front left support column 112, with front prong 124, rear prong 126 and lateral surface 128, forms the front left axle support 122. In like manner, the rear wheel housing 80 is shown with the rear wheel assembly 84 installed. The rear right support column 114 with front prong 154, rear prong 156 and lateral surface 158 forms the rear right axle support 152. Similarly, the rear left support column 116, with front prong 144, rear prong 146 and lateral surface 148, forms the rear left axle support 142.

[0118] With continued reference to FIG. 20, the front right axle end 104 is lodged in the front right axle support 132 and the front left axle end 102 is lodged in the front left axle support 122. The front right axle support 132 is formed to be elastically deformable such that the front right axle end 104 forcibly separates the front prong from the rear prong when thrust therebetween. The same cooperation occurs at the other axle supports. Additionally, the front crossmember 164 and the shoe bottom 54 surrounding the front wheel housing 78 hold the lateral surface 128 of the front left support column 112 and the lateral surface 138 of the front right support column 110 in elastically deformable mutual opposition, such that the front axle 98 forcibly separates them when thrust therebetween. Thus, the front wheel assembly 82 is held firmly in the front wheel housing 78. Corresponding structures cooperate likewise to hold the rear wheel assembly 84 in the rear wheel housing 80.

[0119] With continued reference to FIG. 20, front wheel bearings 168 affix the front wheel 86 to the front axle 98. The front wheel 86 forms a front wheel periphery 92. The front axle 98 holds the front wheel 86 at a fixed location relative to the shoe bottom 54 and in a fixed orientation relative to the shoe bottom 54, the location and orientation being determined by the position of the front left axle end 102 and the front right axle end 104 are held within the front left axle support 122 and the front right axle support 132, respectively. Positioned and oriented in this manner, the front wheel 86 defines a sideways oriented, horizontally oriented front wheel axis of rotation as indicated by arrow Y1. The front wheel periphery 92 and the front wheel axis of rotation define a front wheel radius. Corresponding structures cooperate likewise to hold the rear wheel assembly 84 in the rear wheel housing 80 and to define the rear wheel axis of rotation as indicated by arrow Y2.

[0120] The front axle 98 and rear axle 100 are metal, typically steel. The front wheel 86, rear left wheel 88, and rear right wheel 90 are formed of polyurethane or another suitably hard, resilient and durable material. The bearings are of a type generally available for the manufacture of machinery and sporting goods.

[0121] While the foregoing detailed description has described several embodiments of a roller shoe in accordance with the present invention, it is to be understood that the above description is illustrative only and not limiting of the disclosed invention. Indeed, it will be appreciated that the embodiments discussed above and the virtually infinite embodiments that are not mentioned could easily be within the scope and spirit of the present invention. Thus, the present invention is to be limited only by the claims. 

What is claimed is:
 1. A wheeled shoe for rolling and walking, comprising: a shoe upper; a shoe bottom, said shoe bottom forming a top surface, a bottom surface, a front end, a rear end, a left side, and a right side, a lengthwise axis being defined relative to said front end and said rear end, a sideways axis being defined relative to said left side and said right side, and a vertical axis being defined relative to said top surface and said bottom surface; said shoe bottom forming a heel portion, an arch portion, and a forward portion; said forward portion of said shoe bottom forming at least one substrate-contacting portion; a bottom surface plane being defined by said bottom surface of said heel portion and said at least one substrate-contacting portion, said bottom surface plane being normal to said vertical axis; said shoe bottom forming at least one wheel-supporting means; a plurality of wheel bodies, each wheel body forming a wheel periphery adapted to load-bearing, each wheel body being rotatably disposed on said wheel-supporting means so as to define a wheel axis of rotation, said wheel periphery and said wheel axis of rotation defining a wheel radius, said wheel axis of rotation being oriented approximately parallel to said sideways axis of said shoe bottom; said plurality of wheel bodies defining at least two longitudinally spaced-apart wheel axes of rotation; said wheel peripheries of said at least two wheel bodies defining beneath said at least two longitudinally spaced wheel axes of rotation at least one common tangent; each one of said at least one common tangents passing beneath every one of said at least one substrate-contacting portion formed by said shoe bottom; said plurality of wheel axes of rotation being located rearward of said forward portion of said shoe bottom.
 2. A wheeled shoe as set forth in claim 1, wherein at least one of said plurality of wheel radii is unequal to another one of said plurality of wheel radii.
 3. A wheeled shoe as set forth in claim 2, wherein said unequal ones of said wheel radii belong, respectively, to wheel bodies having longitudinally spaced-apart wheel axes of rotation.
 4. A wheeled shoe as set forth in claim 3, wherein the lesser of said unequal wheel radii belongs to the wheel body having the longitudinally forward of said longitudinally spaced-apart wheel axes of rotation.
 5. A wheeled shoe as set forth in claim 3, wherein the greater of said unequal wheel radii belongs to the wheel body having the longitudinally forward of said longitudinally spaced-apart wheel axes of rotation.
 6. A wheeled shoe as set forth in claim 1, wherein at least one of said plurality of wheel axes of rotation is located at a height different from the height of another of said plurality of wheel axes of rotation, said heights being measured as projections onto said vertical axis.
 7. A wheeled shoe as set forth in claim 6, wherein said unequal heights belong, respectively, to longitudinally spaced-apart wheel axes of rotation.
 8. A wheeled shoe as set forth in claim 7, wherein the lower of said unequal heights belongs to the longitudinally forward wheel axis of rotation.
 9. A wheeled shoe as set forth in claim 7, wherein the higher of said unequal heights belongs to the longitudinally forward wheel axis of rotation.
 10. A wheeled shoe as set forth in claim 1, wherein said plurality of wheel bodies are removably disposed on said wheel-supporting means.
 11. A wheeled shoe as set forth in claim 1, wherein said plurality of wheel bodies are snap-fitted to said wheel-supporting means.
 12. A wheeled shoe as set forth in claim 1, wherein each one of said at least one common tangents intersects said bottom surface plane at a point longitudinally forward of said plurality of wheel axes of rotation. 